In a continuing study of the interrelations between contractions and flow in the small intestine, a project is proposed to extend further the techniques of analytical modeling of wall movements worked out previously. These analytical methods, especially the adaptation of the improved finite element method, will be used to examine motions of mucosal muscle, especially of villus motion, to see the effects on flow of luminal fluid. Data about the dimensions of the villus and other mucosal motions will need to be obtained by further study of the tissues. Also studies will investigate the controls of mucosal movements. A new project to correlate our findings with direct measurements of intestinal function will be initiated. These experiments will analyze and quantitate movements of villi in both spatial and temporal terms. Simultaneously with these measurements we will determine uptake of test molecule by the mucosa and relate this uptake to thickness of the fluid layer overlying the villi and movements of villi.